/Engine/Source/Runtime/WebBrowser/Public/IWebBrowserWindow.h
Notify the browser that a mouse button was released within itFReply::Handled()if the mouse event was handled,FReply::Unhandled()oterwise
[FReply](API\Runtime\SlateCore\Input\FReply) OnMouseButtonUp ( const [FGeometry](API\Runtime\SlateCore\Layout\FGeometry) & MyGeometry, const [FPointerEvent](API\Runtime\SlateCore\Input\FPointerEvent) & MouseEvent, bool bIsPopup )